Sherlock shrugs his shoulders. Moriarty had played this game often enough with him: find the buttons, push liberally.

This was payback.

The consulting detective says nothing as he takes something else out of his pocket. A silver chain made up of little balls, with two circles the size of coins dangling down. There's something engraved on them, but even the distance between the two chairs makes that illegible.

It's a bluff, but his face remains completely impassive.

"I think so, yes."